Since installing Patch C my computer has locked up. The only crashes I experienced with Patch B were crash to desktop. I'd like to reinstall Patch B but no longer have it. Does anyone have an active link? Can I just install over C or do I have to go back to the original?

I'm pretty certain you need to uninstall cIV first, then reinstall and patch up to revB. I had the exact same problem. However, my DVD was released after the revB patch, so I don't have a link for you.

After more searching I found it at http://www.blasteroids.com/games/file_details.cfm/9419/civilization_iv. I will try to install over Rev C.

I installed A over B, worked fine.